The present invention relates to vehicle situational awareness display systems, and more particularly to a vehicle display system that depicts a vehicle's position in relation to one or more exclusion zones.
Moving-map display systems have been used to enhance the situational awareness of the operators of ground vehicles and to assist in the movement of these vehicles along a desired route. The desired route may be specifically indicated or a general map may be provided from which the operator can distinguish the desired route. The presentation of the vehicle's position is provided on a display device and typically consists of a symbol representing the aircraft positioned on the display in relation to symbols representing the ground features surrounding the vehicle's position. The features represented may include the physical boundaries of roadways or pathways defined by paved areas, buildings or other permanent structures, natural features such as vegetation and bodies of water, signs, and markings such as roadway center stripes.
In order to determine the relationship of the vehicle symbol to the map representation, a position of the vehicle in relation to a reference point on the map is shown. This also assumes that the position of each feature of the map is established in relation to that reference point. Therefore, the moving-map display system interfaces with or incorporates a precise position location system, which may be a satellite based system such as the Global Positioning System or a terrestrial based system such as LORAN, that in conjunction with widely available computer processing capability can readily provide location with respect to the earth's surface.
Moving-map display systems have been used to improve situational awareness including applications in ground, marine, and air navigation. A database of the desired features to be represented on the display device is transmitted to the moving-map display system or is entirely encoded within the system itself. The representation of each of these features (designated in total as the “map”) is positioned relative to the symbol representing the vehicle. The designation of the system as a moving-map display system implies that when the vehicle is in motion, the vehicle symbol remains fixed on the display while the map moves so the vehicle symbol remains correctly positioned on the portion of the map (and its features) being displayed. The vehicle symbol can be fixed at the center of the display or may be biased downward if more of a forward view from the vehicle is desired.
In particular, in an airport setting, an aircraft map may be defined by an aircraft surface database showing the runways or other travel paths available for an aircraft. Aircraft surface databases are typically represented by a series of points which define line segments that form a runway or taxiway centerline. The displaying of these line segments, along with the aircraft position representation, can provide the airport moving map display which can be used by the pilot to steer the aircraft along the runway and taxiway centerlines.
Aircraft surface databases further include information representative of width of the runway or taxiway from the centerline such that an aircraft crew can ascertain how close the aircraft gear is to the edge of the runway or taxiway. Accordingly, the aircraft surface databases also include the width of each runway and taxiway to allow calculation of runway and taxiway edge lines to represent the runway or taxiway as a rectangle.
However, runway and taxiway intersections can create an issue for the above defined model. Depending on the complication of the intersection (e.g., 5 or six way intersection), additional processing is required to transform a rectangular segment, represented by endpoints and a width, into a true representation of the intersection.
What is needed is a system and method for representing an aircraft map that does not require additional processing and smoothing to create a true representation. What is further needed is such a system and method where the aircraft map is represented based on the particular aircraft and an attribute of the aircraft.